fuel pressure

Hey guys im about to setup up my first turbo rig on my 96 honda accord ex. Base fuel pressure is 40-47psi (without vaccum hose). And im going to use a FMU for my fuel managment.. I know i should probably get a chipped ecu and run a program but im going to do it this way for my first time to get used to turbo...My question is does anyone know about where my fuel pressure should be at for like 6 and 8 pounds of boost... i know that the different fmu pressure springs (like 8:1,10:1,12:1) cause the fuel pressure to go up that amout for every pound of boost, but what FMU pressure should i use? im probably going to have a all stock fuel system becides fuel pump, and dsm 450 injectors.. Hopefully that made since to you guys... Get back to me on this one, thanks mekal.

don't waste your time. for the cost of an fmu, you can have a chipped ecu.

PRESSURE is NOT VOLUME.

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Don't be cheap an FMU will end up costing you allot more money in the long run. Plus, you can't run 450cc injectors on a stock ecu. Your engine will be getting almost double the fuel at idle and part throtte.

I could pick up an fmu for 80 bucks but you guys do got a good point. Ive already done shit tons of research on ecus, chipping, crome and what not, i jus thought i would go the cheap route lol.. Im not the best with electonics/computers but i gess practice makes perfect.. Do you guys know witch program to tune with is most user friendly?

If you are running a turbo only run a 1:1 FP reg. The whole idea of it is that if boost goes up 5lb fuel pressure goes up 5lb BUT in the manifold because it has 5lb of positive pressure the fuel is still only coming out of the injector at the standard pressure, Changing the fuel pressure to get more fuel (adding10lbs more fuel pressure for 5lbs of boost gives you 5lbs more fuel pressure) isnt the way to go as many injectors have an optimum pressure for the best spray pattern (ie bosch) and it is a very crude way and unrefined way of richening a fuel map.